Adjustable support structure



oct. 24, 1960 `A, L, JOHNSON 2,526,666

ADJUSTABLE SUPPORT STRUCTURE Filed Jan, 11;-1946 2 ShetS'f-Sheet 2INVENTOR ALV/NL. JOHNSON @www MTORNEYA Patented Oct. A24, 1950 UNITEDSTATES PATENT y OFFIC ik' l52,526,666 I y l ADJUSTABLE SUPPORT STRUCTURE'l Y Alvin L. Johnson, Worcesten'l'viass. v,A'pplicatimJarman' 11, 1946,serial No. 646,541

7 Cia'ims. (ol. ca -121) This invention relates to adjustable supportsin general and it is the principal object of the in vention to provide asupport such as a table, chair, lap board, etc., the height of which isreadily adjustable. Y

Several persons of varying heights in a house hold may wishto use thesame table, chair, or

ironing board,V or the same person may use the `same at usual heightwhen doing certain things but Will want the table o rboard at a lowerlevel when doing something else. It is an important object of myinvention to provide a table, chair, or any board the height of whichcan be changed easily by the user merely by depressing a convenientpedalor lever.

It is another object of my invention to control the height of a supportby a mechanism readily released to permit lowering thereof but soconstructed that it Will slip and remain in any desired position whenthe support is raised.

The present support is carried by two pairs of vlegs one pair of whichispivoted to one end of the support. The other pair of legs is connectedto the support by an improved sliding attachment which acts not only topermitr sliding but also frictionally resists too rapid descent ofkv thesupport When thel pedal is released.

.Itis a more specific object of the invention to vconnect the 'bottomsof the aforesaid twopairs of legs by a friction lockfreleasable by thepedal. Two springs of unequalstrengths vact on the lock, one normallyholding it in locking position but being overpoweredby the otherspringto move lthe lock to unlocked. position vwhen the p e'dal isA Itis amore particular part of the invention `to locate the lock and p artsassociated in it in a housing which is so located as to engage the pivotof the legs and thus prevent bending of the control and locking rodswhen the support is collapsed for storage purposes.

, Withthese and other objects in view which .will appear as.the-descriptionproceeds my in -vention residesin` the combinationandfarrange- Aof illustration.

Fig. 5 is a plan View looking in the direction' of arrow 5, Fig. 1,parts being broken away;

Fig. 6 is a horizontal section on line 6 6, Figfll,

Fig. '7 is an enlarged vertical section on line 1 1, Fig. 6, i

Fig. 8 is a vertical section on line S-, Fig. '7, Figs. 9 and l0 arediagrammatic side eleva# tions showing the manner of lowering andraising, respectively, the support shown in Fig. 1, and Fig. l1 showsthe preferred form of` support collapsed and standing on end for storageposes. u

This invention is usable with any supportssuch as tables, chairs,boards, benches, etc., ofA any nature, but it is disclosed herein asbeing applied to an ironing board merely for purposes of clarityReferring particularly to Figs. l, 5 and, I have shown the board properon which ironing opera; tions are performed at I0, a pair of primary` orcontrol legs Il and I2, and a second pair of sece' ondary or slidinglegs I3 and I4. A bolt 'Eliserves as a common pivot for the legs and maybesurrounded by front and back spacers I6 and I1, and an intermediatespacerjl, seeFig. 5. j' Ahbearing frame 2|] is secured at'ZI to theunderside of board jm, see Fig.;4, and has pivoted thereto at ,22 theupper ends of the primary legs. y Extending along the underside of jboard l0' i s a guide bar or rail 2.5 spaced below. the bottom of theboard by washers or spacers` 26 and held Ato the board by vbolts or thelike 21 which .pass

v through the ends of the rail and the washers.

strip 32from the edges of which depend reinforcing ang'es 33. .It is inthe llatter that the aforesaid slots: 28 are formed, and these flangesare on opposite sides of a Verticalline Apassing throught alignedpivots3l. In this way I Vinsure smooth sliding of the cross `bar along the`rail while the bar contacts board i!. The` rail isv preffferably'rnetallic and is sufficiently resilient to ex upwardly under theWeight ofthe board to effect the aforesaid frictional engagement. i

The mechanism for adjusting the height of the board I0 is shown moreparticularly in Figs. lj 6, 7 and'8. As shown in Figs. l and ,the bottom3 ends of the primary legs are connected together by a short bolt 35from which the legs ll and i2 diverge upwardly toward their pivots 22. Ashort distance above bolt 35 is a second somewhat longer bolt 36 whichserves as a pivot for a pedal 31 and the left end of a bar 38 of channelform, see Fig. 8, and having upturned edges or anges 39. The bar 38 maybe made of metal and near that end of it adjacent to the secondary legshas secured thereto a housing 4!! having front and vback vertical wallsAll and 42 connecting with Laterally eX- right and left end walls vd3andlll. tending feet 45 on the end walls are secured to the bottom ofchannel bar 35-at 45. The relation of the housing and bar 3B is showninFigs. 7 and 8.

As seen in Fig. 6 the secondary legs are connected by a. brace 3 to thecenter of which is secured an angle bearing 5l. A lock rod 52 hasone endthereof bent and extended through bearing 5|I to have pivotal connectionwith the latter. Rod 52 extends away from brace 55 and passes throughslide bearings or preferably closely tting holes 53 and 54 in the rightand left end Walls 43 and M, respectively= and projects some distance tothe left of the housing a0, see Figs. 1, 6 and 7.

A second rod 55 is pivoted at to the pedal above pivot bolt 35 andextends to the right and into housing lil), see Figs. 1 and '7, where itis bent laterally to form an eye 57 lying close to end wall 43 andsurrounding rod 52. Between the eye 51 and the left end wall lie arethree movable members lcomprising a lock plate 55, a relatively strongcompression spring @l between eye 5l and plate 60, and a relatively weakspring 52 between the lock plate and the left end wall d5.. Acylindrical stop'63 concentric with the lock rod 52 has a right handstop surface 64 lying preferably in a plane perpendicular to rod 52 andpositioned to engage the lock plate and hold it square across rod 52when strong spring El is caused to exert considerable force on the lockplate. The latter has a hole 65 therein through which passes lock rod 52and of a diameter slightly greater than that of rod 52. The lock platehas a broad lower edge Sfor engagement with the bar 38 as shown in Fig.8, and a stop 61 secured to bar 38 may be used to limit motion of thelock plate E!) to the right, see Fig. 7.

As shown in Figs. 7 and 8, parts of the top E8 of the housing, rear wall52, and left end wall 44 (Fig. 7) areremoved to provide an opening '69which permits entry of eye 5'! on the control rod 55 into the housing.Opening 55 also facilitates assembly of the springs and lock plate onthe, lock rod 52.if the latter is inserted through the end wall 43`after the vhousing has been secured to the bar 33. The parts in thehousing, however, can be assembled as indicated in Fig. '7, after whichthe housing can be secured to bar 38.

Assuming that the board is in the stable position shown in Fig. 1,.weakspring 52 will be expanded to hold the lock plate 5S in the full lineposition shown in Fig. .7 in which position the bottom of the lock platewill be against stop 51 and weak spring 52 will hold the lock inclined.When the lock is thus placed the lower left edge of hole 65yfrictionally engages the underside of the lock rod 52 and the lattertogether with bar 38 forms in effect a link of given length and holdsthelegs against spreading.

When it is desired to lower the board lt. the

thereby rocking the pedal in a counter-clockwise direction as viewed inFig. l and moving control rod 55 to the left from the normal to thereleasing position thereof. The eye 5l thereupon slides to the leftalong lock rod 52 and compresses strong spring 6|. thereby overpoweringthe weak spring and moving the locking plate 5i] to the dotted lineposition of Fig. 7 against the stop surface 54. The lock rod 52 is nowunlocked and can slide through the lock plate, and by holding the leftor adjacent end of the board i5 the user can lower the board to thedesired level by movement in the direction of arrow a, Fig. 9, afterwhich the pedal is released and the parts return to the locking positionshown in Fig. 7, full lines. The board IQ will now remain in its newposition shown in dot and dash lines, Fig. 9.

During lowering of the board lil the bar or head 29 will slidefrictionally along the rail 25 to resist too rapid a descent of theboard if the user should not have a im hold on it. Also, the legs i3and. i4 slide along the floor and thus supply additional frictionresisting downward movement of the board. The latter, however, willordinarily be heavy enough to move down when the 'pedal is lowered andovercome the frictional resistances mentioned.

When the board is to be raised the userplaces her foot on the bottoms ofthe control legs near the Ybolt 35, and! then raises the board asindicated by arrow b, to .the dotted position of Fig. l0. During thisoperation the lock rod slides to the left, Fig. 7, through the lockplate without requiring release ofthe lock.. The. lock plate willprevent reverse motion of the lock rod t0 the left, and the board willremain in its raised position. Raising of the board'may be easiler ifthe user placesher foot on the lower ends of the control legs and thendepresses the pedal, since this procedure will movethe lock plate tounlocking position and the lock rod can slide through it easily.

Fig. 11 shows the board collapsed and standing on end for storagepurposes. When the board is to be put away the pedal will be depresseduntil theboard falls to a position close to the floor, after which itcan be Vstood on end as shown in Fig. l1. In the collapsedposition thehousing engages the pivot bolt I5 and thus prevents bending of thecontrol and lock rods if excessive'pressure should be accidentallyexerted on the board. The lock rod islong enough to permit thiscollapsing. Y

From the foregoing it willbe seen that I have provided an ironing boardwith pairs of legs pivoted together andoonnected in pairs by a linkVariable as to vlength for the purpose of adjusting the height of theboard. The. link extends between the lower ends of the legs andpreferably does not project beyond them, hence there is no danger thatthe user willtrip over it, or the pedal hy which the lock is released.The board can be folded and stored as suggested in Fig. 1l.. When theboard is folded the housing will prevent the -pivot boltv I5 fromengaging'and bending the con- Having thus described my invention it Willbe' seen that changes and modications may.v be made therein by thoseskilled in the art without departing from the spirit and scope of theinvention and I do not wish to be limited to the details hereindisclosed. but what I claim is:

. 1. Adjustable supporting .means comprising, crossed pairs of legspivoted together two members slidable relatively to each other andlocated below the point of crossing of said pairs of legs,

one member operatively connected to one of said pairs of legs and theother member operatively connected to the other pair of legs, lock meansnormally locking said members together to prevent separation of thelower ends of said pairs of legs, a pedal pivotally mounted with respectto one of said pairs of legs, and connections between said pedal andlock means eifective when the pedal is depressed to move said lock toabnormal position to unlock said members and permit relative slidingmovement of the latter. in a direc-l f tion corresponding to separationof the lower ends of said pairs of legs.

2. Adjustable supporting means for a board or the like, cross pairs oflegs pivoted together and supporting the board at their upper ends, theboard due to the weight thereof tending to separate the lower ends ofsaid pairs of legs,'a lock rod member operatively connected to the lowerend of one of said pairs of legs, a holding bar member operativelyconnected to the lower ends of the other pair of legs and having asliding connection with the lock rod member,'a lock mounted on one ofsaid members normally locking said member against motion in a directioncorresponding to separation of the lower ends of said pairs of legs, .apedal movably supported by the lower ends of one of said pairs of legs,and a control rod connected to said pedal and guided and supported byone of said members and effective when the pedal is depressed to causesaid lock to unlock said lock rod, whereupon said lock rod is capable ofsliding movement with respect to said housing means in a directioncorresponding to separation of the lower ends of said pairsof legs.

3. In adjustable supporting means for a member, cross pairs of legspivoted together and supporting the member at their upper ends, the'member due to the weight thereof tending kto separate the lower ends ofsaid pairs of legs, a holdingbar, a pivotal-connection between said barand the lower ends of one of said pairs of legs, a pedal pivotallymounted on said pivotal connection, a lock rod operatively' connected tothe lower ends of the other pair of legs, lock means normally inposition to lock the holding bar and lockVV rod together to preventrelative movement thereof in a direction corresponding to separation ofthe lower ends of the pairs of legs, and a control rod for the lockoperatively kconnected to the pedal and effectivewhen the latter isdepressed to cause said lock to move to unlocked position, therebyenabling the lock rod to move relatively to the holding bar in adirection corresponding Vto separation of the lower ends of said pairsof legs.

4. Adjustable supporting means comprising, crossed pairsof legs pivotedtogether two members slidably connected to each other andlocated belowthe point of crossing-of said pairs of legs, one member operativelyconnected to one of said pairs of legs and the other member operativelyconnected to the other pair of legs, adjacent ends of said membersmutually supporting each other, lockA means operatively secured to onemember for engagement with the other member, resilient means normallyholding the lock means in position to lock the members together toprevent separation of the lower ends of said pairs of legs, and pedalmeans held in normal position by said resilient means and operative whenmoved to releasing position to move said lock means against the actionof said resilient means to abnormal position to unlock said members, thelatter thereupon being capable of relative sliding movement to permitseparation of the lower ends of said pairs of legs, the resilient meansreturning the lock means to normal position to lock said memberstogether upon movement of the pedal means to the normal positionthereof.

5. In adjustable supporting means for a member, crossed pairs of legspivoted together and supporting the member at their upper ends, themember due tothe weight thereof tending to separate the lower ends ofsaid pairs of legs, holding bar means operatively connectedto the lowervends of one of said pairs of legs, a lock rod operatively connected tothe lower ends of the other pair of legs and having sliding relationwith respect to the holding bar means, a lock operatively secured tosaid holding bar means surrounding the lock rod, a spring normallyholding the lock in locked relation with respect to the lock rod, asecond spring stronger than the rst named spring normally ineffective tomove the lock to unlocked position, and pedal operated control meansextending into operative relationship with respect to said second springand effective when moved in a given direction to cause said secondspring to overpower the first named spring and move the lock to unlockedrelation with respect to said lock rod, whereupon said lock rod iscapable of movement relatively to the holding bar means in a directioncorresponding to separation of the lower ends of said pairs of legs.

6. A continuously adjustable supporting device comprising crossed pairsof legs pivoted together,a

. rod connected to each of said leg pairs, a tilting fric vent relativeseparating motion thereof so that the leg pairs cannot separate, saidlock means being eiTective to provide for easy, smooth, and continuousrelative advance of the rods to allow the leg pairs to move toward eachother, and means to release the lock means.

7. A continuously adjustable supporting device comprising crossed pairsof legs pivoted together, a rod connected to each of said leg pairs, alock means on the rods and being effective normally to prevent relativeseparating motion thereof s0 that the leg pairs cannot separate, saidlock means being effective to provide for easy, smooth and continuousrelative advance of the rods to allow the leg pairs to move toward eachothenmeans to release the lock means, means to normally urge the lockmeans to locking position, a control .means to operate the lock releasemeans remotely from the lock means, one of the rods Vbeing a lock rodand the lock means compris- (References on following page) REFERENCESCITED UNTTED STATES PATENTS Number Name Date Kilbourne Mar. 4, 1879 KingJune 27, 1882 Parmelee July 19, 1892 Finnegan et a1 Apr. 3, 1900 10Number 8 Name Date Messer N'ov. 14, 1905 Thorner Oct. 11, 1910 Hone Dec.7, 1915 Danielson Mar. 30, 1920 Stevenson May 17, 1932 Swanson July 26,1932 Williams May 8, 1934 Johannsen Aug. 31, 1937 Monnot Feb. 8, 1944

